The photon mapping technique can be used in POV-Ray for making stunningly beautiful images with light reflecting
and refracting from objects. By default, however, reflected and refracted light does not affect media. Making photons
interact with media can be turned on with the media keyword in the photons block inside global_settings.

To visualize this, let's make the floor of our room reflective so that it will reflect the beam of light coming
from the window.

Firstly, due to how photons work, we need to specify photons { pass_through } in our scattering media
container box so that photons will pass through its surfaces.

Secondly, we will want to turn photons off for our fill-light since it's there only for us to see the interior of
the room and not for the actual lighting effect. This can be done by specifying photons { reflection off }
in that light source.

Thirdly, we need to set up the photons and add a reflective floor to the room. Let's make the reflection colored
for extra effect: